This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Relaxation is a summation of process by which magnetization decays over time. T1 and T2 are the characteristic parameters used to describe the process. The experiments are two series of HSQC mesurements modified so that the magnetization will remain on the nitrogen a different ammount of time in each measurement. T2 and T1 will be extracted by fitting a series of decline spctra in signal strength over relaxation time to a decreasing exponential.